{"id":"CVE-2026-72061","state":"PUBLISHED","title":"net: sit: require CAP_NET_ADMIN in the device netns for changelink","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: sit: require CAP_NET_ADMIN in the device netns for changelink\n\nipip6_changelink() operates on at most two netns, dev_net(dev) and the\ntunnel link netns t->net. They differ once the device is created in or\nmoved to a netns other than the one the request runs in. The rtnl\nchangelink path checks CAP_NET_ADMIN only against dev_net(dev), so a\ncaller privileged there but not in t->net can rewrite a tunnel that\nlives in t->net.\n\nGate ipip6_changelink() on rtnl_dev_link_net_capable() at its top,\nbefore any attribute is parsed. sit was the one tunnel type not covered\nby the recent series that added this check to the other changelink()\nhandlers.","publishedAt":"2026-08-15T05:52:15.823Z","updatedAt":"2026-10-19T21:19:25.695Z","severity":{"score":8.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"cb41b308e9d867725d965b291dd085028e36a480","versionType":"git"},{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"c5a0ae895432596b2f464172da8218e2d84e2932","versionType":"git"},{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"7d139dec96691cde96cb40ed293e2d13d994fb4f","versionType":"git"},{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"388ccffbd2e7e5e4271f291085a7451865705305","versionType":"git"},{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"c0ea1aedb37bb979e864ed7787975434bbd9db73","versionType":"git"},{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"3118e97dae533fb45964b87bbed1801afcff7c65","versionType":"git"},{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"99ae3248b33df94201915d9c32e7470cdf08cfcd","versionType":"git"},{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"27ccb68e7cccead5d8c611665a45d23032d468b3","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv6/sit.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.11","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.11","versionType":"semver"},{"version":"5.10.261","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.212","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv6/sit.c"]}],"references":["https://git.kernel.org/stable/c/cb41b308e9d867725d965b291dd085028e36a480","https://git.kernel.org/stable/c/c5a0ae895432596b2f464172da8218e2d84e2932","https://git.kernel.org/stable/c/7d139dec96691cde96cb40ed293e2d13d994fb4f","https://git.kernel.org/stable/c/388ccffbd2e7e5e4271f291085a7451865705305","https://git.kernel.org/stable/c/c0ea1aedb37bb979e864ed7787975434bbd9db73","https://git.kernel.org/stable/c/3118e97dae533fb45964b87bbed1801afcff7c65","https://git.kernel.org/stable/c/99ae3248b33df94201915d9c32e7470cdf08cfcd","https://git.kernel.org/stable/c/27ccb68e7cccead5d8c611665a45d23032d468b3"],"weaknesses":["CWE-862"],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/72xxx/CVE-2026-72061.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-72061","state":"PUBLISHED","datePublished":"2026-08-15T05:52:15.823Z","dateUpdated":"2026-10-19T21:19:25.695Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-09T03:40:39.903Z"},"containers":{"cna":{"title":"net: sit: require CAP_NET_ADMIN in the device netns for changelink","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: sit: require CAP_NET_ADMIN in the device netns for changelink\n\nipip6_changelink() operates on at most two netns, dev_net(dev) and the\ntunnel link netns t->net. They differ once the device is created in or\nmoved to a netns other than the one the request runs in. The rtnl\nchangelink path checks CAP_NET_ADMIN only against dev_net(dev), so a\ncaller privileged there but not in t->net can rewrite a tunnel that\nlives in t->net.\n\nGate ipip6_changelink() on rtnl_dev_link_net_capable() at its top,\nbefore any attribute is parsed. sit was the one tunnel type not covered\nby the recent series that added this check to the other changelink()\nhandlers."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"cb41b308e9d867725d965b291dd085028e36a480","versionType":"git"},{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"c5a0ae895432596b2f464172da8218e2d84e2932","versionType":"git"},{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"7d139dec96691cde96cb40ed293e2d13d994fb4f","versionType":"git"},{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"388ccffbd2e7e5e4271f291085a7451865705305","versionType":"git"},{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"c0ea1aedb37bb979e864ed7787975434bbd9db73","versionType":"git"},{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"3118e97dae533fb45964b87bbed1801afcff7c65","versionType":"git"},{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"99ae3248b33df94201915d9c32e7470cdf08cfcd","versionType":"git"},{"version":"5e6700b3bf98fe98d630bf9c939ad4c85ce95592","status":"affected","lessThan":"27ccb68e7cccead5d8c611665a45d23032d468b3","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv6/sit.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.11","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.11","versionType":"semver"},{"version":"5.10.261","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.212","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv6/sit.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/cb41b308e9d867725d965b291dd085028e36a480"},{"url":"https://git.kernel.org/stable/c/c5a0ae895432596b2f464172da8218e2d84e2932"},{"url":"https://git.kernel.org/stable/c/7d139dec96691cde96cb40ed293e2d13d994fb4f"},{"url":"https://git.kernel.org/stable/c/388ccffbd2e7e5e4271f291085a7451865705305"},{"url":"https://git.kernel.org/stable/c/c0ea1aedb37bb979e864ed7787975434bbd9db73"},{"url":"https://git.kernel.org/stable/c/3118e97dae533fb45964b87bbed1801afcff7c65"},{"url":"https://git.kernel.org/stable/c/99ae3248b33df94201915d9c32e7470cdf08cfcd"},{"url":"https://git.kernel.org/stable/c/27ccb68e7cccead5d8c611665a45d23032d468b3"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - Exploitation requires RTM_NEWLINK/RTM_SETLINK changelink over a local rtnetlink socket; ipip6_changelink is only reachable from rtnl configuration, not from received IPv4/IPv6 packets processed by ipip6_rcv.\nAC:L - Once a SIT device exists with t->net differing from dev_net(dev) (IFLA_LINK_NETNSID newlink or IFLA_NET_NS_FD migration), a single deterministic netlink changelink bypasses the missing check with no race or memory-layout dependency.\nPR:L - The rtnl entry path requires CAP_NET_ADMIN only in dev_net(dev), obtainable by an unprivileged local user via unshare --user --map-root-user --net; no CAP_NET_ADMIN in the sticky link netns t->net is required.\nUI:N - The attack is fully programmatic through netlink from the attacker's own process; no victim action such as mounting a filesystem, opening a file, or clicking is required.\nS:C - Authorization is checked against dev_net(dev) while ipip6_changelink mutates tunnel state in t->net via ipip6_tunnel_update, crossing from the attacker's net/user namespace into another tenant's or the host's network namespace.\nC:H - An attacker can rewrite IFLA_IPTUN_LOCAL/REMOTE, link, fwmark, and encap parameters to redirect IPv6-in-IPv4 traffic to an attacker-controlled endpoint and read all tunneled payloads in the victim link netns.\nI:H - Unauthorized changelink updates live tunnel endpoints, underlay link, encap ports, and 6rd prefix/relay settings in t->net, enabling redirection and injection of IPv6 traffic carried over the SIT tunnel.\nA:H - Rewriting tunnel remote/local addresses, underlay device, or 6rd parameters breaks 6to4, 6rd, and cross-netns IPv6 connectivity, causing sustained loss of service for every workload depending on the affected SIT tunnel."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T05:39:54.286Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.11","versionEndExcluding":"5.10.261"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.11","versionEndExcluding":"5.15.212"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.11","versionEndExcluding":"6.1.178"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.11","versionEndExcluding":"6.6.145"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.11","versionEndExcluding":"6.12.97"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.11","versionEndExcluding":"6.18.40"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.11","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.11","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-72061","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:51:08.793068Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-862","lang":"en","type":"CWE","description":"CWE-862 Missing Authorization"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T21:19:25.695Z"}}]}}}